[geeks] Stupid Electronics Help...

Nick B nick at pelagiris.org
Mon Dec 31 12:10:17 CST 2012


Non-audio specific relays have a possibly no longer deserved reputation for
*terrible* audio quality, which may be a reason to avoid them.
I can't see any of the pics, so I have no idea what the circuitry involved
looks like, but I like the idea of hijacking the built-in amp *WAY* better
than the other options proposed.  I assume you have considered and
reasonably rejected the FM tuner method?  It isn't pretty, but it works.
BTW, nice to see you posting Mike.
Nick


On Mon, Dec 31, 2012 at 12:41 PM, Jonathan Katz <jon at jonworld.com> wrote:

> I found this which gives instructions on wiring directly into the factory
> amp,
> without having to use my relay and a second amp. I may go this route. Why
> do
> they use resistors and capacitors instead of a diode?
>
> http://www.volvo-forums.com/index.php?showtopic=1497&st=0
>
>
> On Dec 31, 2012, at 1:52 AM, rjtoegel <rjtoegel at gmail.com> wrote:
>
> > Also, you can drive five speakers from a stereo amp. The front and back
> can
> be
> > fed by each channel by using a fader control and the center front is just
> > between the hot leads from each channel.  That gives a difference between
> the
> > right and left channels.  Only problem is that in today's cars, the
> speaker
> > grounds may not be grounded.    Sometimes messing with the speaker wires
> will
> > make the car computer throw out weird errors since the audio may be tied
> in
> > with the computer.  If there are three wires from each speaker, don't
> mess
> > with it!  Trouble will ensue.
> >
> > Bob
> >
> > Sent from my iPod
> >
> > On Dec 30, 2012, at 9:13 PM, Jonathan Katz <jon at jonworld.com> wrote:
> >
> >> Thanks, everyone!
> >>
> >> I found a DPDT at Radio Shack which seems to have solved my "crisis"
> > other
> >> than the fact I mis-read the label and wired it up wrong. I gave up for
> >> tonight and will resume my shenanigans once it gets a tad warmer out.
> >>
> >> The whole goal is to add an AUX in to my wife's Volvo. Her Volvo has a
> > fancy
> >> sound system that uses the MOST fiber-optic stuff, so you can't just
> patch
> >> something in like with typical systems. Using one of the radio/FM
> >> mini-broadcasters is a PITA and the quality is horrid since the car has
> an
> >> antenna that is integral with the tailgate(!)
> >>
> >> Going through my pile of parts I had a spare car audio amplifier. I
> bought
> > it
> >> years ago at the firesale at Circuit City when they were going bankrupt.
> >>
> >> I put together an aux-in 3.5mm port on the dash and ran wires to where
> the
> >> MOST amp is under the passenger seat. I also ran a 12V switch on the
> dash
> > and
> >> wired the hot 12V wire to under the seat.
> >>
> >> The goal was to have the relay turn off the MOST amp (which is why when
> the
> >> relay is deactivated that pole should remain closed so operation is
> normal)
> >> and power on my amp. Then my amp would pump sound to the existing
> speakers,
> >> splicing into the existing wires to existing speakers. Because my spare
> amp
> > is
> >> only two channel and I'm powering five channels (LR, RR, LF, RF, and
> Center
> >> Front) I was planning on using diodes in-line on each channel so that
> with
> > the
> >> new amp hooked up I don't wind up bridging my entire set of speakers.
> >>
> >> My diode idea should work, right?
> >>
> >> On Dec 30, 2012, at 6:54 PM, rjtoegel <rjtoegel at gmail.com> wrote:
> >>
> >>> That's what I said. It's probably easier to find a dual throw than
> just a
> >>> plain NC. Even Rat Shack carries them.
> >>>
> >>> Bob
> >> _______________________________________________
> >> GEEKS:  http://www.sunhelp.org/mailman/listinfo/geeks
> > _______________________________________________
> > GEEKS:  http://www.sunhelp.org/mailman/listinfo/geeks
> _______________________________________________
> GEEKS:  http://www.sunhelp.org/mailman/listinfo/geeks


More information about the geeks mailing list